Cellulose-containing composite

ABSTRACT

A cellulose-containing composite contains 20-99% by weight of a fine cellulose and 1-80% by weight of at least one low-viscosity water-soluble dietary fiber selected from the group consisting of 1) a hydrolyzed gallactomannan, 2) an indigestible dextrin and 3) a mixture of a polydextrose and xanthan gum and/or gellan gum, wherein the total amount of gellan gum and xanthan gum is 0.1% by weight or more but less than 3% by weight of the composite, in which composite the average particle size of the fine cellulose is 30 μm or less when the composite is dispersed in water.

TECHNICAL FIELD

The present invention relates to a cellulose-containing composite. Moreparticularly, the present invention relates to a cellulose-containingcomposite which comprises a particular fine cellulose and alow-viscosity water-soluble dietary fiber and which is superior infeeling when taken into the mouth, and which is also superior in shaperetainability, and fluidity when made into a liquid food, etc. andfurther in effects as dietary fiber or as oil and fat substitute.

BACKGROUND ART

Cellulose has been used in foods for various purposes of, for example,imparting suspension stability, emulsion stability, shape retainabilityor cloudiness, or for adding dietary fiber. However, when cellulose isused alone as a stabilizer or the like, there have been cases that theaddition effect is insufficient or the cellulose-added food givesslightly rough feeling to the tongue. Natural dietary fibers areordinarily a composite of a water-insoluble dietary fiber and awater-soluble dietary fiber and these two kinds of dietary fibers differin action in the intestinal tract. Therefore, the dietary fiber materialused in food is preferred to be a combination of the above two kinds ofdietary fibers. However, neither dietary fiber material nor combineddietary fiber material is currently available which has a low viscositysuitable for use in food, which has good feeling when taken into themouth, and which has high stability.

In JP-B-57-14771 is described a composite comprising a microcrystallinecellulose, a dispersing agent (a gum) and a disintegrating agent inparticular proportions. The composite has a high viscosity dependingupon the kind of gum used and, therefore, it has given paste-likeviscous feeling when taken into the mouth, in some cases. For example,Avicel RC-591 (trade name) (a product of Asahi Chemical Industry Co.,Ltd.), which is a commercially marketed crystalline cellulosepreparation, comprises a microcrystalline cellulose and, as a dispersingagent, sodium carboxymethylcellulose and, when dispersed in water in a3% concentration, gives a high viscosity of 1,200 mPa·.

In JP-B-6-75474 is described a composition comprising a microcrystallinecellulose and galactomannan gum. The galactomannan gum used in thiscomposition is an ordinary gum not subjected to any decompositiontreatment and acts as a binder for the microcrystalline cellulose.Therefore, when the composition is stirred in water, the compositiononly swells, causes no disintegration into particles, and maintains theoriginal state. Therefore, the composition has low suspension stabilityin water although it gives in-mouth feeling similar to that of fat andis suitable as a fat substitute for use in food.

In JP-A-6-135838 is described an oral or tube fed nutritious compositioncomprising a microcrystalline cellulose (as a water-insoluble dietaryfiber) and an enzymatically hydrolyzed guar gum (as a water-solubledietary fiber). In this composition, the microcrystalline cellulose andthe enzymatically hydrolyzed guar gum are not in a composite form but ina simple mixture; therefore, the rough feeling of the microcrystallinecellulose is not sufficiently suppressed and the in-tube flowing-downproperty has not been sufficient.

In JP-A-7-173332 and JP-A-7-268129 are described composites comprising afine cellulose and a hydrophilic substance and/or a water-soluble gum,which contain particles having particle diameters of 10 μm or more, inan amount of 40% or less and which have a colloidal content (which is ayardstick for the amount of fine particles) of 65% or more. In theliterature, polydextrose is shown as an example of the hydrophilicsubstance, and xanthan gum is shown as an example of the water-solublegum. These composites, however, have a high colloidal content andaccordingly high viscosity; therefore, when used in a food such as adrink or the like in an amount of 1% or more, they give viscous feelingand, when used in a tube fed liquid diet, it has been difficult to allowthem to flow down at a sufficient speed.

In the above-mentioned JP-A-7-173332 and JP-A-7-268129 are shown dextrinas an example of the hydrophilic substance. Dextrin is a group ofintermediates formed when starch is subjected to partial hydrolysis bythe action of acid, enzyme, heat or the like, and it is often referredto in industry, as pyrodextrin obtained by dry method (Sogo ShokuhinJiten (6th edition), pp. 617-618 (1989), edited by Yoshito Sakurai andpublished from Dobun Shoin). In the above literature, hydrolyzed starchis also mentioned; therefore, the dextrin mentioned in the literaturerefers to pyrodextrin. Incidentally, as is well known in the art,pyrodextrin includes white or yellow dextrin obtained by subjectingstarch to pyrolysis using an acid catalyst, and British gum obtained bysubjecting starch to pyrolysis using no acid, and each dextrin containsan indigestible component. However, the content of the indigestiblecomponent is at most about 40%, and more than half is digestible (K.Ohkuma et al., Denpun Kagaku, 37 (2), pp. 107-114 (1990)). That is,substances generally known as dextrin have been digestible. In contrast,the dextrin usable in the present invention which is indigestible asmentioned later, is different from the dextrin mentioned in the aboveliterature, and has a meaning as a dietary fiber material in the presentinvention because it is indigestible.

In JP-A-7-70365 is described a composite of a fine cellulose and apolydextrose, which contains particles having particle diameters of 10μm or more, in an amount of 40% or less and which has a colloidalcontent of 50% or more. This composite has a low viscosity but containsno stabilizer such as gellan gum or the like; therefore, it has nolong-term suspension stability. Moreover, in the composite, thecellulose particles are fine and tend to interact with milk protein,etc., and the polydextrose has no sufficient effect for reducing of theinteraction; therefore, the system using the composite has tended tocause flocculation. In the literature is also described the use ofdextrin. This dextrin, however, is different from the indigestibledextrin used in the present invention, for the same reason as mentionedabove.

In WO 98/33394 is described a texture agent for food, obtained by mixinga microcrystalline cellulose and a polydextrose in water and drying theresulting mixture. The polydextrose is used only in the claims of theliterature, and only maltodextrin is used in the Examples, etc.Therefore, the effect of the composition using a polydextrose is unclearfrom the above literature alone. However, the composition using apolydextrose is presumed to have insufficient stability at a lowconcentration, because the composition is thought to have the sameeffect as the composition using maltodextrin and because it is shown inthe literature that the composition using maltodextrin gives a lowviscosity at a low concentration but gives rise to precipitation ofcellulose and resultant separation into two layers. The literature alsohas a description regarding a composition using xanthan gum incombination. Since the amount of xanthan gum used is 3% or more, thecomposition has a high viscosity of 525 mPa·s or more when made into a2% suspension. In WO 98/33394 is disclosed neither data nor technicalidea of cellulose-containing composite of low viscosity and highstability.

DISCLOSURE OF THE INVENTION

The present invention is intended to provide a cellulose-containingcomposite which has a low viscosity and excellent suspension stabilitywhen dispersed in water, which is good in feeling when taken into themouth, superior suspension stability, shape retainability, and fluiditywhen made into a tube fed liquid diet, etc., and which has an effect ofwater-insoluble dietary fiber and an effect of water-soluble dietaryfiber; and a food composition containing the composite.

The present inventors found out that a composite comprising a particularfine cellulose and a low-viscosity water-soluble dietary fiber has a lowviscosity when dispersed in water and, since the fine cellulose has asmall average particle size, gives no viscous feeling when used in foodsand contributes to food stability such as shape retainability or thelike. The present invention has been completed based on these findings.

The present invention lies in the following embodiments.

(1) A cellulose-containing composite comprising 20-99% by weight of afine cellulose and 1-80% by weight of at least one low-viscositywater-soluble dietary fiber selected from the group consisting of 1) ahydrolyzed galactomannan, 2) an indigestible dextrin and 2) a mixture ofa polydextrose and xanthan gum and/or gellan gum (the total amount ofgellan gum and xanthan gum is 0.1% by weight or more but less than 3% byweight of the composite), in which composite the average particle sizeof the fine cellulose is 30 μm or less when the composite is dispersedin water.

(2) A composite according to the above (1), which has a viscosity of 300mPa·s or less when made into a suspension of 3% by weight of thecomposite.

(3) A composite according to the above (1), which has a colloidalcontent of less than 65% when the low-viscosity water-soluble dietaryfiber is a mixture of a polydextrose and xanthan gum and/or gellan gum.

(4) A composite according to the above (1), which has a colloidalcontent of less than 65%.

(5) A composite according to the above (1), wherein the water-solubledietary fiber is a mixture of a polydextrose and xanthan gum and/orgellan gum (the total amount of gellan gum and xanthan gum is 0.1% byweight or more but less than 3% by weight of the composite) and whichcomposite has a colloidal content of less than 65%.

(6) A process for producing a cellulose-containing composite, whichcomprises mixing, in a wet state, 20-99% by weight of a fine celluloseand 1-80% by weight of at least one low-viscosity water-soluble dietaryfiber selected from the group consisting of 1) a hydrolyzedgallactomannan, 2) an indigestible dextrin and 3) a mixture of apolydextrose and xanthan gum and/or gellan gum (the total amount ofgellan gum and xanthan gum is 0.1% by weight or more but less than 3% byweight of the composite) and then drying the resulting mixture. Thisprocess is suitable as a process for producing any of thecellulose-containing composites of the above (1) to (5).

(7) A process for producing a cellulose-containing composite, whichcomprises simultaneously mixing and attriting, in a wet state, 20-99% byweight of a depolymerized cellulose and 1-80% by weight of at least onelow-viscosity water-soluble dietary fiber selected from the groupconsisting of 1) a hydrolyzed gallactomannan, 2) an indigestible dextrinand 3) a mixture of a polydextrose and xanthan gum and/or gellan gum(the total amount of gellan gum and xanthan gum is 0.1% by weight ormore but less than 3% by weight of the composite) and then drying theresulting mixture. This process is suitable as a process for producingany of the cellulose-containing composites of the above (1) to (5).

(8) A food containing a cellulose-containing composite set forth in anyof the above (1) to (5).

(9) A food containing a cellulose-containing composite set forth in anyof the above (1) to (5), wherein the composite is disintegrated anddispersed in the form of individual fine cellulose particles.

(10) A food according to the above (9), which is a tube fed liquid diet.

BEST MODE FOR CARRYING OUT THE INVENTION

The cellulose-containing composite of the present invention is not onlya mixture of the powder of fine cellulose with the powder of alow-viscosity water-soluble dietary fiber or the like but also theparticles which contain, within one particle, one or more fine celluloseparticles and the low-viscosity water-soluble dietary fiber, andoptionally other components, wherein the low-viscosity water-solubledietary fiber is present around any one of the fine cellulose particlesor dried powder composed of a group of such particles.

The cellulose-containing composite of the present invention, when placedin water and stirred, is not dispersed in water in the form of thecomposite, but is disintegrated and dispersed in the form of individualfine cellulose particles.

When the present cellulose-containing composite is placed in water in a1% concentration and dispersed by stirring, the fine cellulose of thecomposite has an average particle size of 30 μm or less. In this case,the proportion of fine cellulose particles having particle sizes of 10μm or more is preferably 80% or less, in the particle size distribution.More preferably, the average particle size is 20 μm or less and theproportion of particles having particle sizes of 10 μm or more is 70% orless. Even more preferably, the average particle size is 3-10 μm and theproportion of particles having particle sizes of 10 μm or more is 50% orless. When the average particle size is more than 30 μm, the compositegives rough feeling to the tongue when taken into the mouth in the formof a drink or a food, and further is low in properties such as stabilityand the like. As the average particle size of fine cellulose is madesmaller, there tends to be less rough feeling to the tongue. However,when the average particle size is less than 3 μm, the amount ofcolloidal content and thus the viscosity increases in some cases, whichcase is not desirable.

The cellulose-containing composite of the present invention has a lowviscosity. It means that the composite has a low viscosity, preferably300 mPa·or less as measured for a 3% aqueous dispersion. When theviscosity is more than 300 mPa·, the composite tends to have viscousfeeling when taken into the mouth. When the composite is made into, inparticular, a tube fed liquid diet, it is difficult to allow the liquiddiet to flow at a certain or high speed, specifically at a speed of 200g/hr or higher when a liquid diet containing about 1.5% of the compositeis allowed to flow down through a tube having an inner diameter of 1 mmor less. Further, the tube fed liquid diet tends to clog the tube at theclamp portion when the flow speed is adjusted to a certain value, forexample 170 g/hr, by throttling the clamp. The viscosity is preferably100 mPa·or less, more preferably 50 mPa·or less.

The fine cellulose in the present invention is cellulose particleswherein the average particle size is 30 μm or less. In this case, theproportion of fine cellulose particles having particle sizes of 10 μm ormore is 80% or less in the particle size distribution. Preferably, theaverage particle size is 20 μm or less and the proportion of finecellulose particles having particle sizes of 10 μm or more is 70% orless. More preferably, the average particle size is 3-10 μm and theproportion of fine cellulose particles having particle sizes of 10 μm ormore is 50% or less.

The hydrolyzed galactomannan is obtained by using, as the raw material,guar gum, locust bean gum or the like, all of which can be collectedfrom bean seeds and are a galactomannan, and subjecting it to partialdecomposition of galactomannan main molecular chain with an enzyme orthe like. Since the galactomannan main molecular chain is decomposed,the hydrolyzed galactomannan is characterized in that its aqueoussolution has a low viscosity as compared with the galactomannan beforedecomposition. The hydrolyzed galactomannan gives a viscosity of 300mPa·or less, preferably 100 mpas or less, particularly preferably 10mPa·s or less when dissolved in water in a 10% concentration.Incidentally, guar gum not subjected to any enzymatic hydrolysis gives ahigh viscosity of about 3,000 to 4,000 mPa·at a 1% concentration.Preferred as the hydrolyzed galactomannan is a guar gum enzymatichydrolysis product for the availability. Its commercial products include“Sunfiber” (trade name) (a product of Taiyo Kagaku Co., Ltd.), “FiberonS” (trade name) (a product of Dainippon Pharmaceutical Co., Ltd.), etc.

The indigestible dextrin is obtained, for example, by heating a starchin the presence of an acid to obtain a pyrodextrin and then subjectingthe pyrodextrin to enzymatic hydrolysis or further to fractionation withan ion exchange resin. The indigestible dextrin is an indigestiblesubstance of highly branched structure wherein the dietary fiber has anaverage molecular weight of about 500 to 3,000, the glucose residue isbonded by an α-1,4-, α-1,6-, β-1,2-, β-1,3- or β-1,6-glucoside bond, andpart of the reducing terminal is levoglucosan (1,6-anhydroglucose).Commercial products of the sparingly digestible dextrin include “PineFiber” (trade name), “Fibersol 2” (trade name) (both are products ofMatsutani Chemical Industry Co., Ltd.), etc. These products arecharacterized in that they give a low viscosity when dissolved in waterand, unlike ordinary starches, are indigestible. In the presentinvention is used an indigestible dextrin which gives an aqueoussolution of low viscosity similar to that given by the hydrolyzedgalactomannan. As starches generally giving a low viscosity aqueoussolution, there are hydrolyzed starch (HCS: hydrolyzed cereal solid),dextrin and maltodextrin; however, these are different from theindigestible dextrin used in the present invention because they aredigestible. In the present invention is used an indigestible dextrincontaining a dietary fiber component, i.e. an indigestible component inan amount of 50% or more, preferably 70% or more.

Polydextrose is a glucose polymer in which glucose molecules arerandomly bonded to one another and which is highly branched. Thepolydextrose is hardly digested by human digestive enzymes and thereforefunctions as a dietary fiber. Polydextrose has a relatively lowmolecular weight, is well soluble in water and gives an aqueous solutionof low viscosity; therefore, the polydextrose is in wide use as awater-soluble dietary fiber. Polydextrose can be produced, for example,by mixing glucose with a small amount of sorbitol, adding a small amountof citric acid, and heating the resulting mixture under reducedpressure. As usable commercial products, there are “Litesse”, “LitesseII”, “Litesse III” (all are trade names and products of Cultor FoodScience Co., Ltd.), etc.

Polydextrose gives about the same low viscosity as the hydrolyzedgalactomannan or the indigestible dextrin; however, being inferior instability per se, it must be used in admixture with xanthan gum and/orgellan gum.

Xanthan gum has such a structure that the main chain has a molecularstructure similar to that of cellulose wherein glucose residues arebonded in a straight chain by β-1,4-glucoside bond, and thattrisaccharides formed by bonding of α-D-mannose, β-D-glucuronic acid andβ-D-mannose are bonded, as side chains, to every other one of theglucose residues of the main chain. To the trisaccharide are bondedacetyl groups and pyruvic acid groups. Xanthan gum has a molecularweight of about 1,000,000 or more.

Gellan gum is a straight chain polymer containing, as constituent units,four kinds of saccharide molecules, i.e. β-D-glucose having 1,3-bond,β-D-glucuronic acid having 1,4-bond, β-D-glucose having 1,4-bond andα-L-rhamnose having 1,4-bond, wherein one glyceryl group and 1/2 (on anaverage) acetyl group are bonded to the glucose residue having 1,3-bond.This gellan gum is called native type gellan gum. It has a molecularweight of about 600,000 to 700,000. As usable commercial products, thereare “Kelcogel LT-100” (trade name) (a product of San-Ei Gen F.F.I.,Inc.), etc.

Both xanthan gum and gellan gum are characterized in that they aresoluble in water and give an aqueous solution of high viscosity. Xanthangum and gellan gum may be mixed with polydextrose singly or inadmixture. In the mixture with polydextrose, Xanthan gum and/or gellangum is used in an amount of preferably 10% by weight or less. In thepresent invention, there is used, as such a mixture, one giving, whenmade into a 1% aqueous solution of Xanthan gum and/or gellan gum, aviscosity of 350 mPa·s or less, preferably 100 mPa·s or less,particularly preferably 10 mPa·s or less. The total amount of gellan gumand xanthan gum used must be 0.1 to 3% by weight of the presentcomposite. When the total amount is less than 0.1% by weight, theresulting composite does not have satisfactory stability. When the totalamount is more than 3% by weight, increased stability is obtained butlow viscosity is impaired.

The cellulose-containing composite of the present invention comprises20-99% by weight of a fine cellulose and 1-80% by weight of at least onelow-viscosity water-soluble dietary fiber selected from the groupconsisting of 1) a hydrolyzed galactomannan, 2) an indigestible dextrin,and 3) a mixture of a polydextrose and xanthan gum and/or gellan gum(the total amount of gellan gum and xanthan gum is 0.1% by weight ormore but less than 3% by weight of the composite). When the amount ofthe fine cellulose is less than 20% by weight, the composite shows nosufficient effect as a stabilizer when used, for example, for impartingshape retainability in baking a cake. When the amount of the finecellulose is more than 99% by weight, the composite gives rough feelingto the tongue or dry (not moist) feeling in the mouth. When the amountof the low-viscosity water-soluble dietary fiber is less than 1% byweight, the fine cellulose of the composite is not dispersed intoindividual particles when the composite is placed in water and stirred.When the amount of the low-viscosity water-soluble dietary fiber is morethan 80% by weight, the composite shows no sufficient effect as astabilizer and moreover gives viscous feeling to the tongue.

The cellulose-containing composite of the present invention comprisespreferably 40-90% by weight of a fine cellulose and 10-60% by weight ofa low-viscosity water-soluble dietary fiber, particularly preferably50-85% by weight of a fine cellulose and 15-50% by weight of alow-viscosity water-soluble dietary fiber.

In the cellulose-containing composite of the present invention, it ispossible to as necessary use, besides the fine cellulose and thelow-viscosity water-soluble dietary fiber, various components usable infoods, such as monosaccharide, oligosaccharide, sugar alcohol, starch,soluble starch, hydrolyzed starch, oil and fat, protein, table salt,other salt (e.g. phosphate), emulsifier, thickener and stabilizer,acidulant, spice, food color and the like. In order to control, inparticular, the dispersing state of the composite, it is effective touse a thickener and stabilizer used in foods (e.g. xanthan gum,carrageenan, sodium carboxymethylcellulose, pectin or gellan gum), asaccharide and a starch (e.g. soluble starch or hydrolyzed starch), adietary fiber (e.g. hydrolyzed pectin) singly or in combination. Thesecomponents may be added during or after production of the presentcomposite. The amounts of these components used should be appropriatelydetermined in view of the required balance of functions (e.g. stability)and viscosity; however, when a hydrolyzed galactomannan or anindigestible dextrin is used as the low-viscosity water-soluble dietaryfiber, use of 3% or less of xanthan gum or 1% or less of gellan gum cangive a favorable result. A particularly preferred amount of the abovecomponents is 0.1 to 2.5% by weight based on the composite.

The cellulose-containing composite of the present invention is preferredto have a low colloidal content. In the present invention, “colloidalcontent” is a physical property value that is obtained unambiguously bythe method disclosed on page 26, line 25 through page 27, line 27,infra, for the fine cellulose composite according to the presentinvention. Since a high colloidal content gives a high viscosity, thecolloidal content is preferably 85% or less, more preferably less than65%, particularly preferably 5 to 50%.

Also, when the present composite comprises 20-99% by weight of a finecellulose and 1-80% by weight of a mixture of a polydextrose and xanthangum and/or gellan gum (the total amount of gellan gum and xanthan gum is0.1% by weight or more but less than 3% by weight of the composite), thecolloidal content is preferred to be less than 65%. A colloidal contentof 65% or higher results in a high viscosity and an increased reactivitywith milk protein particles in an acidic environment (this invitesreduced stability). Therefore, the colloidal content is preferably 5 to50%, particularly preferably 10 to 40%.

The present composite comprising a fine cellulose and a low-viscositywater-soluble dietary fiber is not a mere mixture of a powdery finecellulose and a powdery low-viscosity water-soluble dietary fiber, butis a composite obtained by mixing a fine cellulose and a low-viscositywater-soluble dietary fiber in a wet state, that is, in a slurry, paste,gel or cake state and then drying the resulting mixture. It is importantthat by conducting the mixing in a wet state, the surfaces of the finecellulose particles are made well compatible with the low-viscositywater-soluble dietary fiber. It is speculated that after the dryingstep, an interaction occurs between the fine cellulose particles and thelow-viscosity water-soluble dietary fiber and hence, in case these finecellulose particles are dispersed into individual particles by stirringin water, a part of the low-viscosity water-soluble dietary fiber isremained attached to the surface of the fine cellulose particles. As aresult, the aqueous dispersion of the composite has a decreasedviscosity and shows reduced clogging at the portion of a clamp whenflowing down in a tube, than a simple mixture of the above components.The water content in the mixture before drying is preferably about 30%by weight or more of the total weight of the mixture. A low watercontent is not preferred because a longer time is required forsufficient mixing of the fine cellulose and the low-viscositywater-soluble dietary fiber. The water content is more preferably about50% or more.

The process for producing the cellulose-containing composite of thepresent invention is described specifically.

The cellulose-containing composite of the present invention can beobtained, for example, by subjecting a cellulose material (e.g. woodpulp, refined linters, regenerated cellulose or cereal- or fruit-derivedvegetable fiber) to a depolymerization treatment (e.g. acid hydrolysis,alkali oxidative decomposition, enzymatic hydrolysis, steam explosiondecomposition, hydrolysis by subcritical or supercritical water or acombination thereof) to obtain a cellulose having an average degree ofpolymerization of 30 to 375, then attriting the cellulose by applying amechanical shear (a shear force) to make it into fine cellulose, addingthereto a low-viscosity water-soluble dietary fiber and mixing them, anddrying the resulting mixture. It is particularly preferred to add alow-viscosity water-soluble dietary fiber to the depolymerized cellulosematerial, then conducting attrition and mixing simultaneously byapplying a mechanical shear (this is wet co-attrition), and drying theresulting material to make a fine cellulose-containing composite. Thepresent cellulose-containing composite may also be obtained bysubjecting a cellulose material (e.g. wood pulp or bacterial cellulose)to a weak chemical treatment (not an ordinary chemical treatment), thenconducting wet attrition or pulverizing by applying a mechanical shearto obtain a fine fibrous cellulose or a powdery cellulose, addingthereto a low-viscosity water-soluble dietary fiber, mixing and/orattriting them in the presence of water, and drying the resultingmaterial to make a fine cellulose-containing composite.

The attritor used for wet attrition is appropriately selected dependingupon the amount of water present in the attrition system and theintended degree of cellulose fineness achieved by attrition.

For example, when a sufficient mechanical shear is applied so as toobtain a fine cellulose having an average particle size of 8 μm or less,a media agitating mill can be used (e.g. wet vibration mill, wetplanetary vibration mill, wet ball mill, wet roll mill, wet coball millor wet beads mill), a wet paint shaker, a high-pressure homogenizer, orthe like. Effective as the high-pressure homogenizer is a type wherein aslurry is introduced into a small diameter orifice at a pressure ofabout 500 kgf/cm² or more and face-to-face collision is allowed to takeplace at a high flow speed. When the above mill is used, the optimumsolid concentration in slurry differs depending upon the kind of mill,but is appropriately about 3 to 25% by weight.

When a mechanical shear is applied so as to obtain a fine cellulosehaving an average particle size of 5 to 30 μm, and when a slurry havinga solid content of about 3 to 30% by weight is attrited, an attritor ora mixer can be used such as colloid mill, continuous ball mill,homogenizer, homomixer, propeller mixer or the like. When a cake havinga higher solid content of about 20 to 50% by weight is attrited, therecan be used a kneader, an automated mortar, an extruder or the like. Amicrofibrillated cellulose can be obtained by passing a suspension of acellulose material through a high-pressure homogenizer several times ata pressure of 50 kgf/cm² or more to decrease the fiber diameter to about0.01 to 1 μm, or by treating a suspension of a cellulose material in amedia agitating mill several times. These apparatuses can be used singlyor in combination of two or more to achieve the object of the presentinvention.

The drying of the mixture of a fine cellulose and a low-viscositywater-soluble dietary fiber can be conducted by a known method. However,in practicing the drying, an optimum method should be selected dependingupon the water content in the mixture to be dried and the state of themixture. In drying a slurry mixture, for example, there can be usedspray drying, drum drying, alcohol precipitation, etc. In drying a muddymixture or a rice cake-like mixture, there can be used tray drying, beltdrying, fluidized bed drying, freeze-drying, microwave drying, etc. Inorder to obtain a composite which is improved in solubility andredispersibility in water, it is preferred to spray-dry a slurrymixture. In order to reduce the drying cost, alcohol precipitation,pressing, tray drying which is capable of drying a mixture of high solidcontent, and fluidized bed drying methods are preferred. The upper limitof water content in the dried mixture is preferably 15% by weight orless, particularly preferably 10% by weight or less, more preferably 6%by weight or less in view of the handleability (easiness of handling)and storage stability of the dried mixture.

The dried mixture obtained by drum drying, tray drying, belt drying orthe like has a thin sheet shape or a lump shape. Therefore, it ispreferable that the dried material is pulverized by an appropriatemethod such as impact type pulverizer, jet mill or the like andpowderized to such a degree that almost all the powder can pass througha screen having an opening of 425 μm.

The cellulose-containing composite of the present invention can be usedin various foods. Examples of such foods are drinks such as favoritedrinks (e.g. coffee, black tea, powdered tea, cocoa, adzuki-bean soupwith rice cake and juice), milk-based drinks (e.g. raw milk, processedmilk, lactobacillus drink and soy-milk), nutrient-fortified drinks (e.g.calcium-fortified drink), dietary fiber-containing drinks and the like;ice, such as ice cream, iced milk, soft cream, milk shake, sherbet andthe like; milk products such as butter, cheese, yogurt, coffee whitener,whipping cream, custard cream, pudding and the like; processed oil andfat foods such as mayonnaise, margarine, spread, shortening and thelike; condiments such as soups, stew, sauce, dripping, dressing and thelike; gel- or paste-like foods such as spice pastes (e.g. mustardpaste), jam, fillings (e.g. flour paste), bean jams, jelly and the like;cereal foods such as bread, noodle, pasta, pizza, premixes and the like;Japanese-style and western-style cakes such as candy, cookie, biscuit,hot cake, chocolate, rice cake and the like; marine paste products suchas boiled fish paste, fish cake and the like; livestock products such asham, sausage, hamburger and the like; side dishes taken with cooked riceor bread, such as cream croquette, bean jams for Chinese foods, gratin,dumpling stuffed with minced pork, and the like; delicacies such assalted fish guts, vegetables pickled with sake lees, and the like;liquid diets such as tube fed liquid diet, and the like; and pet foods,and the like.

In these applications, the cellulose-containing composite of the presentinvention acts as a suspension stabilizer, an emulsion stabilizer, athickener and stabilizer, a foam stabilizer, a cloudiness agent, atexture-imparting agent, a fluidity improver, a shape-retaining agent, awater separation-preventing agent, a body-modifying agent, a powderizingagent, a dietary fiber agent, a low calorie agent for oil and fatreplacement, etc. The effects of the present invention can be exhibitedeven when the above foods vary in shape or cooking method as seen inretort foods, powder foods, frozen foods and foods for electronic oven.

Since the present cellulose-containing composite gives a low viscosityand contains a fine cellulose of small particles, it is characterized inthat the food produced with the composite is plain to the tongue, passesthrough the throat comfortably, is low in roughness to the tongue and,therefore, gives good feeling when taken into the mouth.

The present cellulose-containing composite is suitable particularly as adietary fiber material for tube fed liquid diet. Currently, in the artof tube fed liquid diets, it is being attempted to use both awater-soluble dietary fiber and a water-insoluble dietary fiber. Sometube fed liquid diets of this kind are already being marketed but theydo not have such sufficient properties as described below. A tube fedliquid diet is administered to human body through a tube and must flowdown through the tube at a fairly low speed at a constant speed over along period of time. In the above commercial products, however, thereare cases that the water-insoluble component clogs the clamp of the tube(the clamp controls the speed of flowing down). Currently, the tuballiquid food is administered by opening the clamp as necessary toeliminate the clogging. The present cellulose-containing composite givesa low viscosity and the particles of the fine cellulose hardly give riseto flocculation. Therefore, when the present composite is used in a tubefed liquid diet, there occurs substantially no clogging at the clamp ofthe tube. Moreover, since the present composite contains a water-solubledietary fiber and a water-insoluble dietary fiber, the present compositeis highly excellent as a dietary fiber material for tube fed liquiddiet.

When the cellulose-containing composite of the present invention is usedin a food, the main materials of the food and, as necessary, a spice, apH-controlling agent, a thickener and stabilizer, a salt, a saccharide,an oil or fat, a protein, an emulsifier, an acidulant, a food color,etc., they are subjected to mixing, kneading, stirring, emulsification,heating, etc. by using the same apparatus(es) as ordinarily used in theproduction of various foods.

The content of the present cellulose-containing composite in food variesdepending upon the kind of food, etc. but is preferably about 0.01 to15% by weight based on the total weight of the food. The content ispreferably about 0.02 to 3% by weight when the present composite isintended to be used mainly as a stabilizer. The content is preferablyabout 0.5 to 15% by weight when the present composite is intended to beused mainly as a dietary fiber material (for tube fed liquid diet, etc.)or as a material for oil and fat replacement.

Next, the present invention is described in detail below by way ofExamples.

The measurements were made as follows.

Average Particle Size and Proportion of Particles of 10 μm or more inthe composite

(1) Distilled water is added to 3.0 g (as solid content) of a sample tomake the total amount 300 g.

(2) The mixture is dispersed at 15,000 rpm for 5 minutes using AceHomogenizer AM-T (a product of NIPPON SEIKI CO., LTD.).

(3) The resulting dispersion is measured for particle size distributionusing a laser diffraction type particle size distribution measuringapparatus (LA-910, a product of HORIBA SEISAKUSHO CO., Ltd.). “Averageparticle size” is the particle size of 50% cumulative volume, and“proportion of particles having particle sizes of 10 μm or more” is theproportion (%) in volume distribution.

Viscosity of Composite

(1) Distilled water is added to 9.0 g (as solid content) of a sample tomake the total amount 300 g.

(2) The mixture is dispersed at 15,000 rpm for 5 minutes using AceHomogenizer AM-T (a product of NIPPON SEIKI CO., LTD.).

(3) The resulting dispersion is measured for viscosity, using a BL typeviscometer (a product of Tokyo Keiki) at 60 rpm (rotor) at 25° C.(dispersion temperature). The unit of viscosity is mpas.

Colloidal Content of Composite

(1) Distilled water is added to 0.75 g (as solid content) of a sample tomake the total amount 300 (2) The mixture is dispersed at 15,000 rpm for2 minutes using Ace Homogenizer AM-T (a product of NIPPON SEIKI CO.,LTD.).

(3) 10 ml of the resulting dispersion is accurately taken in a weighingbottle and accurately weighed.

(4) 40 ml of the remaining dispersion is transferred into a centrifugetube and is subjected to centrifugation at 2,000 rpm for 15 minutesusing H-300 (a centrifuge produced by Kokusan Enshinki). 10 ml of theupper liquid is accurately taken in a weighing bottle and accuratelyweighed.

(5) The weighing bottles of (3) and (4) are heated in a dryer of 105° C.for 10 hours to subject the contents to evaporation to dryness.

(6) The solid content of (3) is accurately weighed and taken as A g.

(7) The solid content of (4) is accurately weighed and taken as B g.

(8) A correction is made for water-soluble components (the proportion(S%) of the low-viscosity water-soluble dietary fibers and otherwater-soluble substances contained in composite of the total), and thecolloidal content is calculated using the following formula.

Colloidal content (%)=[(B−A×S/100)/(Ax(1×S/100))]×100

EXAMPLE 1

A commercial DP pulp was hydrolyzed in 7% hydrochloric acid at 105° C.for 20 minutes. The resulting acid-insoluble residue was collected byfiltration, and washed to obtain a wet cake (solid content: 40%) ofhydrolyzed cellulose having a degree of polymerization of 195.

This hydrolyzed cellulose and an enzymatically hydrolyzed guar gum(Sunfiber (trade name), a product of Taiyo Kagaku Co., Ltd. having aviscosity of 7 mPa·s when measured at its 10% aqueous solution at 60 rpm(rotor) using a BL type viscometer and a BL adapter) were subjected toattrition and kneading at the ratio (in solid content) shown in Table 1,for 3 hours using a kneader. The kneaded material was dried in a hot airdryer of 60° C. and then pulverized to obtain cellulose-containingcomposites A to D. Each composite was dispersed in water and the aqueousdispersion was measured for average particle size, proportion ofparticles of 10 μm or more, colloidal content and viscosity. The resultsare shown in Table 1. When the aqueous dispersion after the viscositymeasurement was allowed to stand at room temperature for 3 days, therewas no water separation at the top and each dispersion was stable.

EXAMPLE 2

The same operation as in Example 1 was conducted to obtain a wet cake ofhydrolyzed cellulose. Water was added thereto to prepare a cellulosedispersion having a solid content of 10%.

The cellulose dispersion was subjected to a pulverizing treatment bypassing it twice through a media agitation wet grinder (APEX MILL AM-1(trade name), a product of Kotobuki Engineering and Manufacturing Co.,Ltd.) using, as the media, zirconia beads of 1 mm in diameter under theconditions of 1,800 rpm (blade) and 0.4-liter/min (feed rate ofcellulose dispersion), whereby a paste of fine cellulose was obtained.The fine cellulose had an average particle size of 3.4 μm and aproportion of particles of 10 μm or more, of 4.5%.

The fine cellulose and the same enzymatically hydrolyzed guar gum as inExample 1 were mixed at a ratio (in solid content) of 70/30 withstirring, to prepare a dispersion having a total solid content of 13%.Then, the dispersion was casted on an aluminum plate and dried in a hotair dryer at 60° C. Thereafter, the dried material on the aluminum platewas pulverized using a hammer mill to obtain a cellulose-containingcomposite E. The composite E was redispersed in water and the aqueousdispersion was measured for average particle size, proportion ofparticles of 10 μm or more, colloidal content and viscosity. The resultsare shown in Table 1. When the aqueous dispersion after the viscositymeasurement was allowed to stand at room temperature for 3 days, therewas no water separation at the top and the dispersion was stable.

EXAMPLE 3

The same operation as in Example 1 was conducted to obtain a wet cake ofhydrolyzed cellulose. Thereto were added the same enzymaticallyhydrolyzed guar gum as in Example 1 and water to prepare a dispersionhaving a fine cellulose/enzymatically hydrolyzed guar gum ratio of 70/30and a solid content of 16%. The dispersion was treated at 8,000 rpm for15 minutes using TK Homomixer (a product of Tokushu Kika Kogyo K.K.) andthen spray-dried to obtain a cellulose-containing composite F. Thecomposite F was redispersed in water and the aqueous dispersion wasmeasured for average particle size, proportion of particles of 10 μm ormore and viscosity. The results are shown in Table 1. When the aqueousdispersion after the viscosity measurement was allowed to stand at roomtemperature for 3 days, there was no water separation at the top and thedispersion was stable.

EXAMPLE 4

The same operation as in Example 1 was conducted to obtain a wet cake ofhydrolyzed cellulose. This hydrolyzed cellulose, the same emzymaticallyhydrolyzed guar gum as in Example 1, xanthan gum (a product of San-EiGen F.F.I., Inc.) and gellan gum (Kelcogel LT-100 (trade name), aproduct of San-Ei Gen F.F.I., Inc.) were mixed at a ratio (in solidcontent) shown in Table 1. The resulting mixture was subjected to thesame kneading, drying and pulverizing as in Example 1, to obtaincellulose-containing composites G and H. The composites G and H wereredispersed in water and each aqueous dispersion was measured foraverage particle size, proportion of particles of 10 μm or more,colloidal content and viscosity. The results are shown in Table 1. Whenthe aqueous dispersion after the viscosity measurement was allowed tostand at room temperature for 3 days, there was no water separation atthe top and each dispersion was stable.

EXAMPLE 5

A powdered cellulose (KC Flok (trade name), a product of Nippon PaperIndustries Co., Ltd.) and the same enzymatically hydrolyzed guar gum asin Example 1 were mixed at a ratio (in solid content) shown in Table 1.Thereto was added water in an amount of 1.5 times that of the powderedcellulose. The resulting mixture was subjected to the same kneading,drying and pulverizing as in Example 1 to obtain a cellulose-containingcomposite I. The composite I was redispersed in water and the aqueousdispersion was measured for average particle size, proportion ofparticles of 10 μm or more and viscosity. The results are shown inTable 1. When the aqueous dispersion after the viscosity measurement wasallowed to stand at room temperature for 3 days, there was no waterseparation at the top and the dispersion was stable.

Comparative Example 1

The same operation as in Example 1 was conducted for the compositionsshown in Table 1, to obtain cellulose particles a, and a composite b.The resulting cellulose particles and composite were redispersed inwater and the aqueous dispersion was measured for average particle size,proportion of particles of 10 μm or more, colloidal content andviscosity. The results are shown in Table 1. When the aqueous dispersionafter the viscosity measurement was allowed to stand at room temperaturefor 3 days, water separation took place in the aqueous dispersion of thecellulose particles a, at the top 95% portion and, in the aqueousdispersion of the composite b, at the top 32% portion.

EXAMPLE 6

A commercial DP pulp was hydrolyzed in 7% hydrochloric acid at 105° C.for 20 minutes. The resulting acid-insoluble residue was collected byfiltration and washed to obtain a wet cake (solid content: 41%) ofhydrolyzed cellulose. This hydrolyzed cellulose and an indigestibledextrin (Pine Fiber (trade name), a product of Matsutani Kagaku KogyoK.K. having a viscosity of 2 mPa·s when measured for its 10% aqueoussolution at 60 rpm (rotor) using a BL type viscometer and a BL adapter)were subjected to attrition and kneading at the ratio (in solid content)shown in Table 2, for 3 hours using a kneader. The kneaded material wasdried in a hot air dryer at 60° C. and then pulverized to obtaincellulose-containing composites J to L. Each composite was redispersedin water and the aqueous dispersion was measured for average particlesize, proportion of particles of 10 μm or more, colloidal content andviscosity. The results are shown in Table 2. When the aqueous dispersionafter the viscosity measurement was allowed to stand at room temperaturefor 3 days, there was no water separation at the top and each dispersionwas stable.

EXAMPLE 7

The same operation as in Example 6 was conducted to obtain a wet cake ofhydrolyzed cellulose. Thereto was added water to obtain a cellulosedispersion having a solid content of 10%. This cellulose dispersion wassubjected to the same operation as in Example 2 to obtain a paste offine cellulose wherein the average particle size of fine cellulose was3.5 μm and the proportion of particles of 10 μm or more was 4.7%. Thefine cellulose paste and the same indigestible dextrin as in Example 6were mixed at a ratio (in solid content) of 60/40 with stirring, toprepare a dispersion having a total solid content of 13%. Then, thedispersion was casted on an aluminum plate and dried in a hot air dryerat 60° C. Thereafter, the dried material on the aluminum plate waspulverized using a hammer mill to obtain a cellulose-containingcomposite M. The composite M was redispersed in water and the aqueousdispersion was measured for average particle size, proportion ofparticles of 10 μm or more, colloidal content and viscosity. The resultsare shown in Table 2. When the aqueous dispersion after the viscositymeasurement was allowed to stand at room temperature for 3 days, therewas no water separation at the top and the dispersion was stable.

EXAMPLE 8

The same operation as in Example 6 was conducted to obtain a wet cake ofhydrolyzed cellulose. Thereto were added the same indigestible dextrinas in Example 6 and water to prepare a dispersion having a finecellulose/indigestible dextrin ratio of 85/15 and a solid content of16%. The dispersion was treated at 8,000 rpm for 15 minutes using TKHomomixer (a product of Tokushu Kika Kogyo K.K.) and then spray-dried toobtain a cellulose-containing composite N. The composite N wasredispersed in water and the aqueous dispersion was measured for averageparticle size, proportion of particles of 10 μm or more and viscosity.The results are shown in Table 2. When the aqueous dispersion after theviscosity measurement was allowed to stand at room temperature for 3days, there was no water separation at the top and the dispersion wasstable.

EXAMPLE 9

The same operation as in Example 6 was conducted to obtain a wet cake ofhydrolyzed cellulose. The hydrolyzed cellulose, the same indigestibledextrin as in Example 6, xanthan gum (a product of San-Ei Gen F.F.I.,Inc.) and gellan gum (Kelcogel LT-100 (trade name), a product of San-EiGen F.F.I., Inc.) were mixed at a ratio (in solid content) shown inTable 2. The resulting mixture was subjected to the same kneading,drying and pulverizing as in Example 6, to obtain cellulose-containingcomposites O and P. The composites O and P were redispersed in water andeach aqueous dispersion was measured for average particle size,proportion of particles of 10 μm or more, colloidal content andviscosity. The results are shown in Table 2. When the aqueous dispersionafter the viscosity measurement was allowed to stand at room temperaturefor 3 days, there was no water separation at the top and each dispersionwas stable.

EXAMPLE 10

A powdered cellulose (KC Flok (trade name), a product of Nippon PaperIndustries Co., Ltd.) and the same indigestible dextrin as in Example 6were mixed at a ratio (in solid content) shown in Table 2. Thereto wasadded water in an amount of 1.5 times that of the powdered cellulose.The resulting mixture was subjected to the same kneading, drying andpulverizing as in Example 6 to obtain a cellulose-containing compositeQ. The composite Q was redispersed in water and the aqueous dispersionwas measured for average particle size, proportion of particles of 10 μmor more and viscosity. The results are shown in Table 2. When theaqueous dispersion after the viscosity measurement was allowed to standat room temperature for 3 days, there was no water separation at the topand the dispersion was stable.

Comparative Example 2

The same operation as in Example 6 was conducted for the compositionsshown in Table 2, to obtain a composite c. The composite was redispersedin water and the aqueous dispersion was measured for average particlesize, proportion of particles of 10 μm or more and viscosity. Theresults are shown in Table 2.

Comparative Example 3

The cellulose particles a and the same indigestible dextrin as inExample 6 were mixed to obtain a powder d. The powder d was redispersedin water and the aqueous dispersion was measured for average particlesize, proportion of particles of 10 μm or more and viscosity. Theresults are shown in Table 2. When the aqueous dispersion after theviscosity measurement was allowed to stand at room temperature for 3days, water separation took place at the top 94% portion.

EXAMPLE 11

The same operation as in Example 6 was conducted to obtain a wet cake ofhydrolyzed cellulose. The hydrolyzed cellulose, a polydextrose (Litesse(trade name) a product of Cultor Food Science Co., Ltd.), and xanthangum (same as in Example 9) alone or gellan gum (same as in Example 9)alone or a mixture of xanthan gum and gellan gum were mixed at a ratio(in solid content) shown in Table 3. The resulting mixture was subjectedto the same kneading, drying and pulverizing as in Example 6, to obtaincellulose-containing composites R to U. The composites R to U wereredispersed in water and each aqueous dispersion was measured foraverage particle size, proportion of particles of 10 μm or more,colloidal content and viscosity. The results are shown in Table 3. Whenthe aqueous dispersion after the viscosity measurement was allowed tostand at room temperature for 3 days, there was no water separation atthe top and each dispersion was stable.

Comparative Example 4

The same operation as in Example 6 was conducted for the compositionsshown in Table 3, to obtain composites e and f. Each composite wasredispersed in water and the aqueous dispersion was measured for averageparticle size, proportion of particles of 10 μm or more, viscosity andcolloidal content. The results are shown in Table 3.

Comparative Example 5

The same operation as in Example 6 was conducted to obtain a wet cake ofhydrolyzed cellulose. Thereto was added water to obtain a cellulosedispersion having a solid content of 10%. The cellulose dispersion wassubjected to the same operation as in Example 2 to obtain a paste offine cellulose wherein the average particle size of fine cellulose was3.5 μm, the proportion of particles of 10 μm or more was 4.7% and thecolloidal content was 69%. The fine cellulose paste, the samepolydextrose as in Example 11 and the same xanthan gum as in Example 9were mixed at a ratio (in solid content) of 75/20/5 with stirring, toprepare a dispersion having a total solid content of 3.5%. Thedispersion was spray-dried to obtain a composite g. The composite g wasredispersed in water and the aqueous dispersion was measured for averageparticle size, proportion of particles of 10 μm or more, colloidalcontent and viscosity. The results are shown in Table 3. Incidentally,the composite g belongs to the technique disclosed in JP-A-7-268129. Asis clear from Table 3, the aqueous dispersion of the composite g has ahigh colloidal content of 95% and accordingly a high viscosity of 410mpa·s.

Comparative Example 6

A paste of fine cellulose, obtained in the same manner as in ComparativeExample 5, the same polydextrose as in Example 11 and water were mixedto prepare a dispersion having a fine cellulose/polydextrose ratio (insolid content) of 70/30 and a total solid content of 12%. The dispersionwas dried using a drum drier. The resulting film was pulverized toobtain a composite h. The composite h was redispersed in water and theaqueous dispersion was measured for average particle size, proportion ofparticles of 10 μm or more, colloidal content and viscosity. The resultsare shown in Table 3. When the aqueous dispersion after the viscositymeasurement was allowed to stand at room temperature for 3 days, atransparent layer of separated water appeared at the top 11% portion.Incidentally, the composite h is disclosed in JP-A-7-70635.

EXAMPLE 12

A commercial DP pulp was hydrolyzed in 10% hydrochloric acid at 105° C.for 30 minutes. The resulting acid-insoluble residue was collected byfiltration and washed to obtain a wet cake (solid content: 48%) ofhydrolyzed cellulose having a degree of polymerization of 185.

The hydrolyzed cellulose, the same enzymatically hydrolyzed guar gum asin Example 1, an indigestible dextrin (Fibersol 2 (trade name), aproduct of Matsutani Kagaku Kogyo K.K. having a viscosity of 2 mPa·swhen measured for its 10% aqueous solution at 60 rpm (rotor) using a BLtype viscometer and a BL adapter), the same polydextrose as in Example11, the same xanthan gum as in Example 9 and the same gellan gum as inExample 9 were subjected to attrition and kneading at the ratio (insolid content) shown in Table 4, for 3 hours using a kneader. Thekneaded material was dried in a hot air dryer at 60° C. and thenpulverized to obtain cellulose-containing composites V to X. Eachcomposite was dispersed in water and the aqueous dispersion was measuredfor average particle size, proportion of particles of 10 μm or more andviscosity. The results are shown in Table 4. When the aqueous dispersionafter the viscosity measurement was allowed to stand at room temperaturefor 3 days, there was no water separation at the top and each dispersionwas stable.

EXAMPLE 13

Using cellulose-containing composites for the purposes of suspensionstabilization, dietary fiber fortification, etc., nutrient-fortifieddrinks were produced.

There were dispersed, at 10,000 rpm for 10 minutes using TK Homomixer,1.0% by weight of the cellulose-containing composite A, C, G, L, M, P,R, T or X, 3.3% by weight of sodium caseinate, 11.0% by weight ofhydrolyzed starch, 1.4% by weight of sugar, 0.8% by weight of lactose,1.1% by weight of soybean lecithin, 1.0% by weight of a medium chainfatty acid ester, 1.0% by weight of a salad oil and 79.4% by weight ofwater. The resulting material was passed once through a high-pressurehomogenizer at a pressure of 150 kgf/cm² to give rise to homogenization.The resulting material was filled in a heat resisting bottle andsterilized at 121° C. for 30 minutes in an autoclave to obtainnutrient-fortified drinks.

Each drink was examined for viscosity (measured at 60 rpm (rotor) usinga B type viscometer), precipitate formation and rough feeling to tonguewhen taken into mouth. The results are shown in Table 5.

Comparative Example 7

Nutrient-fortified drinks were obtained in the same operation as inExample 13 except that the composite a, g or h was used. Each drink wasexamined for viscosity (measured at 60 rpm (rotor) using a B typeviscometer), precipitate formation and rough feeling to tongue whentaken into mouth. The results are shown in Table 5. The drink using thecomposite g showed no precipitate and no rough feeling to tongue, butwas very viscous and felt like a paste.

EXAMPLE 14

Using cellulose-containing composites for the purposes of, for example,imparting shape retainability or fortifying a dietary fiber, biscuitswere produced.

There were mixed, in a powder state, 30 parts by weight of thecellulose-containing composite A, G, M, P, R, T or X, 300 parts byweight of wheat flour, 100 parts by weight of sugar, 6 parts by weightof sodium bicarbonate and 3 parts by weight of table salt. The mixturewas placed in a planetary mixer. Thereto were added 150 parts by weightof margarine, 30 parts by weight of whole egg (white and yolk) andwater, followed by kneading for 5 minutes. Water was added in an amountshown in Table 6. During the kneading, adhesion of dough to the innerwall of the planetary mixer was observed. The kneaded dough was placedin a refrigerator for one night, then returned to room temperature, andmolded into a shape of 15 mm (thickness) ×30 mm (width) ×15 mm. Themolding was baked in an oven at 160° C. for 20 minutes to obtain variousbiscuits. Each biscuit was observed for shape retainability (sagging)after baking. The biscuit after baking was examined for feeling whentaken into mouth. The results are shown in Table 6.

Comparative Example 8

Biscuits were produced in the same operation as in Example 14 exceptthat the composite a, c or e was used. There were observed the adhesionof dough to the inner wall of planetary mixer during kneading and theshape retainability (sagging) of biscuit after baking. The feeling ofbiscuit when taken into mouth was examined. The results are shown inTable 6.

EXAMPLE 15

Using cellulose-containing composites as a replacement for oil and fat,an emulsion stabilizer, etc., low-fat mayonnaise-like dressings wereproduced.

8.0% by weight of the cellulose-containing composite E, P or T and 37.7%by weight of water were placed in a Hobart mixer and dispersed withstirring. Thereto were added, with stirring, 0.3% by weight of xanthangum and 10.0% by weight of egg yolk. Further, 33.0% by weight of a saladoil was added with stirring. Stirring was continued. Successively, therewere added 7.0% by weight of vinegar, 2.6% by weight of table salt, 0.9%by weight of sugar, 0.4% by weight of a mustard powder and 0.1% byweight of sodium glutamate. The mixture was stirred for about 30 minutesand then passed through a colloid mill for emulsification, to producedressings.

Each dressing was examined for feeling (smoothness, roughness and body)when taken into mouth and thermal stability (emulsion stability when thedressing was placed in a glass bottle and the bottle was immersed in hotwater at 95° C. for 15 minutes). The results are shown in Table 7.

Comparative Example 9

Dressings were produced by the same operation as in Example 15 exceptthat the composite b, e or g was used. Each dressing was examined forfeeling when taken into mouth and thermal stability. The results areshown in Table 7.

EXAMPLE 16

Using cellulose-containing composites for the purposes of dietary fiberfortification, etc., tube fed liquid diets were produced.

There were mixed 1.5% by weight of the cellulose-containing composite C,P or R, 14.2% by weight of hydrolyzed starch, 3.1% by weight of casein,2.1% by weight of powdered skim milk, 1.0% by weight of corn oil, 1.0%by weight of coconut oil, 0.09% by weight of potassium chloride, 0.05%by weight of sodium chloride, 0.05% by weight of magnesium sulfate,0.02% by weight of calcium glycerophosphate, 0.02% by weight of soybeanlecithin, 63 ppm of vitamin C, 20 ppm of vitamin E, 9 ppm of nicotamideand 0.7 ppm of vitamin B1 hydrochloride. Thereto was added 76.87% byweight of hot water having a temperature of 60° C. The mixture wasdispersed at 10,000 rpm for 5 minutes using TK Homomixer. The resultingmaterial was passed once through a high-pressure homogenizer at apressure of 150 kgf/cm² for emulsification. The resulting material wasfilled in a heat resistant bottle and sterilized at 121° C. for 30minutes in an autoclave, to obtain tube fed liquid diets.

To the tip of a tube (inner diameter: 3.4 mm, length: 120 cm) fitted toa polyvinyl chloride-made bag for nutrient feeding was connected anEVA-made tube (inner diameter: 0.88 mm, length: 120 cm) for nutrientfeeding. Then, one liter of the tube fed liquid diet obtained above wasfilled in the bag for nutrient feeding. By throttling a clamp, theflowing-down speed of the tube fed liquid diet was controlled to 170g/hr, and the tube fed liquid diet was allowed to flow down from aheight of 1.2 m. The tube fed liquid diet was measured for appearancewhen filled in the bag, clogging during flowing down, change of flowingspeed, etc. The results are shown in Table 8.

Comparative Example 10

Tube fed liquid diets were produced by the same operation as in Example16 except that the composite b, d, g or h was used. Each tube fed liquiddiet was examined in the same manner as in Example 16. The results areshown in Table 8.

TABLE 1 Composition (wt. %) Aqueous dispersion of Composite Enzyma-Average Particles Com- Fine tically particle of 10 μm Colloidal pos-cellu- hydrolyzed Xanthan Gellan size or more content Viscosity ite loseguar gum gum gum (μm) (%) (%) (mPa · s) Example 1 A 40 60 0 0 7.4 35 188 B 60 40 0 0 8.2 42 — 10 C 75 25 0 0 8.0 38 21 12 D 90 10 0 0 11.0 56 —12 Example 2 E 70 30 0 0 3.6 7.5 83 40 Example 3 F 70 30 0 0 18.2 64 —60 Example 4 G 70 28 2 0 8.4 42 70 80 H 70 29 0 1 8.6 39 — 86 Example 5I 70 30 0 0 15.4 58 — 20 Com- a 100 0 0 0 42.0 86 0 10 parative b 10 900 0 7.6 38 5 8 Example 1

TABLE 2 Aqueous dispersion of Composite Composition (wt. %) AverageParticles Com- Fine Indiges- particle of 10 μm Colloidal pos- cellu-tible Xanthan Gellan size or more content Viscosity ite lose dextrin gumgum (μm) (%) (%) (mPa · s) Example 6 J 45 55 0 0 7.1 25 — 4.0 K 70 30 00 8.5 38 — 5.4 L 85 15 0 0 11.2 55 32 9.5 Example 7 M 60 40 0 0 4.5 7 567.6 Example 8 N 85 15 0 0 14.8 67 — 45 Example 9 O 74 25 1 0 6.9 26 — 40P 74.7 25 0 0.3 7.3 29 42 30 Example 10 Q 60 40 0 0 21.3 82 — 16 Com- c10 90 0 0 6.3 21 3 7.0 parative Example 2 Com- d 70 30 0 0 41.0 83 0 6.3parative Example 3

TABLE 3 Aqueous dispersion of Composite Composition (wt. %) AverageParticles Com- Fine particle of 10 μm Colloidal pos- cellu- Poly-Xanthan Gellan size or more content Viscosity ite lose dextrose gum gum(μm) (%) (%) (mPa · s) Example 11 R 60 38.5 1.5 0 6.5 21 26 27 S 50 49.50 0.5 6.2 19 40 33 T 40 59.2 0.5 0.3 8.5 38 63 47 U 75 23.5 1.5 0 7.5 3232 39 Com- e 10 90 0 0 6.4 21 12 7.2 parative f 70 30 0 0 8.2 37 14 5.5Example 4 Com- g 75 20 5 0 3.7 2.5 95 410 parative Example 5 Com- h 7030 0 0 4.0 10 81 60 parative Example 6

TABLE 4 Aqueous composition of composite Average Particles particle of10 μm Colloidal Compos- Composition (wt. %) size or more contentViscosity ite FC GU ND PD XA GE (μm) (%) (%) (mPa · s) Example 12 V 8010 10 0 0 0 9.5 42 — 8 W 70 10 18 0 2 0 8.2 35 — 15 X 60 0 30 8.5 0 19.6 46 35 16 FC: fine cellulose GU: hydrolyzed guar gum ND: indigestibledextrin PD: polydextrose XA: xanthan gum GE: gellan gum

TABLE 5 Viscosity Roughness to Composite (mPa · s) tongue PrecipitateExample 13 A 24 No No C 24 No No G 210 No No L 32 No No M 22 No No P 120No No R 95 No No T 170 No No X 51 No No Comparative a 32 Yes Yes Example7 g 1560 No No h 250 No Yes

TABLE 6 Amount of Shape water retain- added Adhesion ability (parts byduring after Feeling Composite weight) kneading baking in mouth ExampleA 40 No Good Good 14 G 50 No Good Good M 50 No Good Good P 55 No GoodGood R 50 No Good Good T 45 No Good Good X 50 No Good Good Compar- a 60No Good Rough to ative tongue Example 8 c 30 Yes Shape was Poor meltinglost. in mouth e 30 Yes Shape was Poor melting lost. in mouth

TABLE 7 Feeling in mouth Com- Smooth- Rough- Thermal posite ness nessBody stability Example 15 E Good No Good No separation of water or oil PGood No Good No separation of water or oil T Good No Good No separationof water or oil Compar- b Good No Insuf- Slight separation of ativeficient both water and oil Example 9 e Good Yes Insuf- Slight separationof ficient both water and oil g Good Yes Exces- No separation of sivewater or oil

TABLE 8 Com- Flowing- posite Appearance down property Example 16 C GoodSlight clogging took place twice. Clogging was eliminated by opening theclamp, and the whole volume flowed down. P Good The whole volume floweddown with no clogging. R Good The whole volume flowed down with noclogging. Comparative b A white precipitate layer Owing to severe clog-Example 10 appeared at the bottom ging, flowing-down 6% portion. at aconstant speed was impossible. d A white precipitate layer Owing tosevere clog- appeared at the bottom ging, flowing-down 4% portion. at aconstant speed was impossible. g Good The high viscosity made itimpossible to achieve a desired flow speed even by full opening of theclamp. h Flocculation took place Complete clogging in the whole portion.tack place 6 times.

Industrial Applicability

The cellulose-containing composite of the present invention comprises aparticular fine cellulose, a hydrolyzed galactomannan, an indigestibledextrin, a polydextrose and a stabilizer (e.g. xanthan gum and gellangum) at particular proportions. Therefore, when dispersed in water, thepresent composite gives a low viscosity and excellent suspensionstability. Accordingly, the food containing the present composite issuperior in feeling when taken into mouth, has superior shaperetainability, flowing-down property when used as tube fed liquid diet,etc., and moreover has very high effects as a dietary fiber material, areplacement for oil and fat, etc.

What is claimed is:
 1. A cellulose-containing composite comprising20-99% by weight of a fine cellulose and 1-80% by weight of at least onelow-viscosity water-soluble dietary fiber selected from the groupconsisting of 1) a hydrolyzed galactomannan, and 2) an indigestibledextrin, in which composite the average particle size of the finecellulose is 30 μm or less when the composite is dispersed in water,which composite has a viscosity of 300 mPa·s or less at 25° C. when madeinto an aqueous suspension of 3% by weight of the composite.
 2. Acomposite according to claim 1, which has a colloidal content of lessthan 65%.
 3. A process for producing a cellulose-containing composite,which comprises mixing, in a wet state, 20-99% by weight of a finecellulose and 1-80% by weight of at least one low-viscositywater-soluble dietary fiber selected from the group consisting of 1) ahydrolyzed galactomannan, 2) an indigestible dextrin and 3) a mixture ofa polydextrose and xanthan gum and/or gellan gum, wherein the totalamount of gellan gum and xanthan gum is 0.1% by weight or more but lessthan 3% by weight of the composite, and then drying the resultingmixture.
 4. A process for producing a cellulose-containing composite,which comprises simultaneously mixing and attriting, in a wet state,20-99% by weight of a depolymerized cellulose and 1-80% by weight of atleast one low-viscosity water-soluble dietary fiber selected from thegroup consisting of 1) a hydrolyzed galactomannan, 2) an indigestibledextrin and 3) a mixture of a polydextrose and xanthan gum and/or gellangum, wherein the total amount of gellan gum and xanthan gum is 0.1% byweight or more but less than 3% by weight of the composite, and thendrying the resulting mixture.
 5. A cellulose-containing compositecomprising 20-99% by weight of a fine cellulose and 1-80% by weight of amixture of a polydextrose and xanthan gum and/or gellan gum, wherein thetotal amount of gellan gum and xanthan gum is 0.1% by weight or more butless than 3% by weight of the composite, in which composite the averageparticle size of the fine cellulose is 30 μm or less when the compositeis dispersed in water, which composite has a viscosity of 300 mPa·s orless at 25° C. when made into an aqueous suspension of 3% by weight ofthe composite, and which composite has a colloidal content of less than65%.
 6. A cellulose-containing composite set forth in any one of claims1, 2 and 5 wherein the composite is contained in a foodstuff.
 7. Acellulose-containing composite set forth in any one of claims 1, 2 and5, wherein the composite is contained in a foodstuff, and isdisintegrated and dispersed in the form of individual fine celluloseparticles.
 8. A cellulose-containing composite set forth in any one ofclaims 1, 2 and 5, wherein the composite is contained in a liquid dietfor tube feeding, and is disintegrated and dispersed in the form ofindividual fine cellulose particles.